2 due in court in Boston after bust tied to designer drug Molly

Police are investigating whether four recent deaths of college students who had used the popular party drug "Molly" are linked to a single bad batch of the substance – and whether it could kill more along the East Coast.

Two men are due in court in Boston on Monday on charges that they sold the designer drug Molly, a purified and sometimes deadly form of Ecstasy that authorities say is gaining popularity.

Police would not say whether the arrests were tied to three recent deaths in the Northeast attributed to Molly — two in New York and a college student from New Hampshire who overdosed and died at the House of Blues club in Boston.

The men due in court, Daniel Milisi, 29, and Joseph Doolin, 36, were arrested during a bust at a Boston bar Friday night. Police told NBC affiliate WHDH that undercover officers arranged to buy Molly from the men, then arrested them.

Emergency room visits linked to Molly, which is usually sold as a white powder in a capsule, have doubled since 2004. City officials in New York shut down a music festival after the two deaths there over Labor Day weekend.

The effects of the drug include high energy, euphoria and increased empathy and can last three to six hours. It has been name-checked recently by Madonna, Miley Cyrus and other artists.